Spirit level with clamping action

ABSTRACT

A spirit level frame is provided with an annular opening. A vial holder includes a pair of spaced clamp members which slip over the frame opening edge and are clamped to the frame, as by tightening screws. To assist the clamp in holding the members together, cooperating ridge and groove means are provided. In addition, projections on the holder and the surfaces of the screws are on an arc of a circle having the same radius as the opening edge for assisting in proper positioning of the holder.

United States Patent 11 1 Johnson 11 3,75,3fll

451 Aug. 7, 1973 SPIRIT LEVEL WITH CLAMPING ACTION [75] Inventor:

[73] Assignee: Johnson Products Company, Inc.,

Milwaukee, Wis.

[22] Filed: Feb. 18, 1971 [21] Appl. No.: 116,383

George A. Johnson, Mequon, Wis.

[56] References Cited UNITED STATES PATENTS l,280,994 l0/l9l8 Hand33/213 Primary Examiner-Louis R. Prince Assistant ExaminerDennis A.Dearing AnorneyAndrus, Sceales, Starke & Sawall [57] ABSTRACT A spiritlevel frame is provided with an annular opening. A vial holder includesa pair of spaced clamp members which slip over the frame opening edgeand are clamped to the frame, as by tightening screws. To assist theclamp in holding the members together, cooperating ridge and groovemeans are provided. In addition, projections on the holder and thesurfaces of the screws are on an arc of a circle having the same radiusas the opening edge for assisting in proper positioning of the 3,167,8702/1965 Streeter.... 33 211 959,296 5/1910 Bodmer 33 213 holdeh FOREIGNPATENTS QR APPLICATIONS 1 Claim 3 Drawing Figures 252,739 9/1948Switzerland 33 213 PATENIED M15 3. 750. 301

INVENTOR GEORGE A.JOHNSON ATTORNEYS SPIRIT LEVEL WITH CLAMPHNGAClfllfibl BACKGROUND AND SUMMARY OF THE INVENTION This inventionrelates to a spirit level, and more particularly to a constructionwherein the vial holder is clamped to the level frame in a unique andimproved manner.

In accordance with the invention, the level frame is provided with anannular opening. The vial holder includes a pair of spaced clamp memberswhich slip over the frame opening edge and are clamped to the frame, asby tightening screws. To assist the clamp in holding the 'memberstogether, cooperating rigid and groove means are provided. In addition,locator means on the holder cooperate with the frame opening edge toproperly position the holder.

DESCRIPTION .OF THE DRAWING The accompanying drawing illustrates thebest mode presently contemplated by the inventor for carrying out theinvention. I

In the drawing:

FIG. I is a plan view of a portion of a level constructed in accordancewith the invention;

FIG. 2 is-a transverse section taken on line 2-2 of FIG. 1; and 1 FIG. 3is a central section taken on line33 of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT Holder 4 is of unitaryconstruction and is made of relatively rigid plastic of any well-knowntype. As shown, holder 4 comprises a pair of slightly flexible generallyplanular semi-circular clamping legs 5 which are joined together attheir inner portions by an elongated holder base 6 which is shorter thanthe diameter of opening 2. The outer edges 7 of legs 5 are arcuate andoverlie the edge portion of frame opening 2.

Holder 4 is adapted to generally diametrically hold a glass or othersuitable level vial 8 therein. For this purpose, a pair of slightlyflexible vial clamps 9 extend outwardly from the ends of base 6 radiallyinwardly from legs 5. Clamps 9 may be of the snap-in type, generallysimilar to those disclosed in Lawrence A. Johnson U.S. Pat. No.3,190,010 entitled SPIRIT LEVEL.

In accordance with the invention, holder legs 5 are spaced apart attheir juncture with base 6, and also throughout when in their parallelunclamped position, a distance slightly greater than the thickness offrame 1 adjacent opening 2. This facilitates slipping of the holder legsover the frame opening edge portion. After this is accomplished, and theholder properly positioned and set as will bev described, screw meansare provided radially inwardly of edge} to pull the peripheral portionsof clamping legs 5 together into tight engagement withframe 1. As shown,the screw means extend through'suitably aligned openings 10 in legs 5,and through frame opening 2, and comprise self-tapping screws 11. Thescrew means could also comprise a bolt and nut arrangement withoutdeparting from the spirit of the invention. v

Any suitable number ofscrew means rnay be utilized, it having been foundthat at least one screwll positioned on each side of the holderstransverse center line 2-2 provides excellent holding action.

In some instances, it has been found desirable to supplement the holdingpower of radially extending clamping legs 5 so that holder 4 will notslide off or ride around opening 2. For this purpose, frictionincreasing means are provided at the interface between legs 5 and theopening edge portion. In this embodiment, the friction increasing meanscomprises an annular groove 12 formedon each opposite face of frame I.Grooves 12 are concentric with and have a larger radius than opening 2.An elongated curved locating ridge I3 is formed on the inner opposedfaces of clamping legs 5, with ridges 113 being of the same radius asgrooves 12 so that they nest therein, as shown.

Further in accordance with the invention, locating or stop means areprovided to limit the radially outward position of holder 4 so thatridges 113 will not overrun grooves 12 during installation. For thispurpose, a pair of spaced projections 14 extend outwardly from the endportions of base 6 between legs 5. Projections 14 and the outer portionsof screw openings 10 are positioned to be on an are 115 of a circle ofequal radius as opening edge 3. Thus, projections 14 and screws 11 willengage edge 3 and properly locate the holder.

The-concept of the invention provides a unique vial holder and clampingarrangement with the level frame. The holder fills approximatelyone-half of opening 2 and can be selectively adjusted to any desiredcircumferential position.

Various modes of carrying out the invention are contemplated as beingwithin the scope of the following claims particularly pointing out anddistinctly claiming the subject matter which is regarded as theinvention.

I claim:

I. A spirit level comprising, in combination:

a. a level frame having an annular opening therein,

said opening defining an edge, and said frame providing an edge portionadjacent said edge,

b. a relatively rigid vial holder disposed in the said opening and withsaid holder including a pair of slightly flexible generally planarsemi-circular clamping legs,

c. an elongated base joining the inner portions of said legs and withsaid base being shorter than the opening diameter,

d. a vial clamp extending from each end of said base and radiallyinwardly from said legs,

e. said legs being spaced apart at their juncture with said base adistance slightly greater than the thickness of said frame,

f. the outer edges of said legs overlying the said edge portion of saidframe opening,

g. and an annular groove formed on each opposite face of said frame andwith said grooves being concentric with and having a larger radius thansaid opening, 7

h. a curved locating ridge formed on the inner opposed faces of theouter edge portions of said legs and nesting in said grooves,

i. a pair of spaced projections extending outwardly from the endportions of, said base between said legs,

j. and screw means extending through said legs to a radius equal to thatof said opening edge so that tighten said holder to said frame, saidprojections and said screw means locatingly k. said projections and theouter surface portion of engage said edge.

said screw means being on an arc of a circle having

1. A spirit level comprising, in combination: a. a level frame having anannular opening therein, said opening defining an edge, and said frameproviding an edge portion adjacent said edge, b. a relatively rigid vialholder disposed in the said opening and with said holder including apair of slightly flexible generally planar semi-circular clamping legs,c. an elongated base joining the inner portions of said legs and withsaid base being shorter than the opening diameter, d. a vial clampextending from each end of said base and radially inwardly from saidlegs, e. said legs being spaced apart at their juncture with said base adistance slightly greater than the thickness of said frame, f. the outeredges of said legs overlying the said edge portion of said frameopening, g. and an annular groove formed on each opposite face of saidframe and with said grooves being concentric with and having a largerradius than said opening, h. a curved locating ridge formed on the inneropposed faces of the outer edge portions of said legs and nesting insaid grooves, i. a pair of spaced projections extending outwardly fromthe end portions of said base between said legs, j. and screw meansextending through said legs to tighten said holder to said frame, k.said projections and the outer surface portion of said screw means beingon an arc of a circle having a radius equal to that of said opening edgeso that said projections and said screw means locatingly engage saidedge.